Pigmented fluoropolymer coatings are widely used today for coating architectural panels. These coatings can provide an attractive finish which will resist fading and chalking for long periods of time. In the production of coating compositions for structural building components, such as metal building panels, there are often competing requirements which must be balanced. Good durability properties such as color retention, mar resistance and chalk resistance are required in the face of severe weather conditions as well as corrosive industrial pollutants. Good flexibility is also needed in order to facilitate fabrication of the metal without loss of the coating's adhesion.
In the coil coating area, the difficulties are exemplified with conventionally utilized PVC plastisol based coating compositions. PVC plastisols are desirable coating vehicles from the standpoint of fabrication, thick film capability, and ability to be formulated with high solids, but generally exhibit poor durability, color retention, chalk resistance and dirt resistance. As a result, compromises must often be made either in terms of ultimate film properties or workability of the coated substrate.
There is, accordingly, a continuing need for improved coatings which give excellent durability as well as allowing fabrication of the coated substrate, thick film capability, and high solids.